Epithelioid leiomyosarcoma

Ooffi, U., Quattrone, P, de Simone, M., Bonavia, L., SegaUn, A., Masi-ni, T., Montorsi, M. Primary multiple epithelioid leiomyosarcoma of the Uver. Hepato-Gastroenterol. 1996 43 1603—1605... 

ELMS, epithelioid leiomyosarcoma ASPS, alveolar soft part sarcoma HMFH, histiocytic malignant fibrous histiocytoma EOS, epithelioid osteosarcoma. 

FIGURE 4.32 Granular cell angiosarcoma Is an uncommon lesion with a differential diagnosis that Includes granular cell tumor, metastatic melanoma, and epithelioid leiomyosarcoma. 

Suster S. Epithelioid leiomyosarcoma of the skin and subcutaneous tissue Glinicopathologic, immunohistochemical, and ultra-structural study of five cases. Am J Surg Pathol. 1994 18 232-240. 

Lopez-Barea F, Rodriguez-Peralto JL, Sanchez-Herrera S, et al. Primary epithelioid leiomyosarcoma of bone Case report and literature review. Virchows Arch. 1999 434 367-371. 

Uterine epithelioid leiomyosarcomas frequently express cytokeratins and lack desmin expression. 

Silva EG, Deavers MT, Bodurka DC, et al. Uterine epithelioid leiomyosarcomas with clear cells Reactivity with HMB-45 and the concept of PEComa. Am J Surg Pathol. 2004 28 244-249. 

Fetal fibroblasts myometrium vascular smooth muscle fetal myocardium vascular endothelial cells selected reticulum cells of lymphatic organs some CD30+ lymphoid cells (rarely) selected leiomyosarcomas, epithelioid hemangioendotheliomas, epithelioid angiosarcomas, primitive neuroectodermal tumors and Ewing s sarcomas, malignant peripheral nerve sheath tumors, and clear cell sarcomas... 

Keratins are regularly found in synovial sarcoma, chordoma, parachordoma, epithelioid sarcoma, and adamantinoma. They are seen less commonly in leiomyosarcoma, malignant peripheral nerve sheath tumors, epithelioid angiosarcoma, and polyphenotypic tumors such as PNET. 

Leiomyosarcoma Adults. Abdomen, pelvis, and various other locations. Spindle or epithelioid cells with areas of smooth muscle differentiation SMA+, HHF35+, desmin+, caldesmon+. EM smooth muscle differentiation... 

In addition to epithelial neoplasms, a number of sarcomas, CNS tumors, small round cell tumors, and a few germ cell tumors may be positive with EMA. These tumors include malignant nerve sheath tumors, synovial sarcoma, leiomyosarcoma, malignant fibrous histiocytoma, epithelioid sarcoma, and chordoma. With the exception of the last two tumors mentioned, EMA immunostaining is focal. 

Although only one primary uterine gastrointestinal stromal tumor (GIST) has been reported, rectal examples may occasionally be mistaken for fibroids. Spindle cell examples would then suggest leiomyoma or perhaps even leiomyosarcoma, and epithelioid varieties could mimic an epithelioid smooth muscle tumor, carcinoma. 

The ambiguous histological differentiation and the controversial immunophenotype of synovial sarcoma make the microscopic diagnosis difficult, especially when the tumor occurs in atypical locations or when the tumor reveals a non-specific immunohistochemical phenotype, which may resemble the immunophenotypic profile of other malignancies such as different types of sarcoma (solitary fibrous tumor, malignant peripheral nerve sheet tumor, fibrosarcoma, epithelioid sarcoma or leiomyosarcoma), metaplastic carcinoma and mesothelioma. Since synovial sarcoma reveals a different clinical behavior than the other mentioned tumors, it is important to discriminate it from these malignancies and additional methods that are more specific may be necessary to confirm the diagnosis. 

Vascular tmnors Angiosarcoma Hemangiosarcoma Epithelioid hemangioendothelioma Leiomyosarcoma Fibrosarcoma Embryonal sarcoma Fibrous histiocytoma Lymphoma (Hodgkin s disease) Lymphoma (non-Hodgkin s disease)... 

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